The bake hardening and ageing behaviour of cold rolled TRIP steels

摘要

The main conclusions can be summarized as follows: 1. A significant increase in the yield stress up to 100 MPa after paint baking simulation was found for both the CMnSi and the CMnAlSi TRIP-aided steel variants in the temper rolled and the 2 % prestrained state. However, a difference in overall strengthening behaviour was found between the two types of steels. 2. Although the decrease of the C content of the retained austenite phase after paint baking simulation suggests that carbides are precipitated from the metastable retained austenite phase at a temperature of 170℃, no evidence was found in the diffractogram of the transformation of austenite to martensite. 3. The differences in strengthening behaviour after a paint baking simulation on the CMnSi and CMnAISi TRIP-aided steels is very likely due to an effect of alloying elements (C, Si, Al) on the mechanical properties ofγ_(ret).